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The purpose of this study is to address the issue that the traditional V-shaped ball valve profile shape is limiting the flow control characteristics in a series structure and to optimize the design profile by proposing an open-hole profile.

This paper proposes a Gaussian process regression surrogate model based on the genetic algorithm optimization of swarm intelligence, combined with the Expected Improvement point addition criterion, to optimize and correct the design profile. The flow regulation performance of the optimized V-shaped regulating ball valve is verified through a combination of numerical simulation and experiment.

The results demonstrate that the optimized V-shaped regulating ball valve has higher flow regulation accuracy and a more stable flow regulation process. After optimization, the flow characteristic curve of the spool is closer to the ideal equal percentage characteristic. The simulation results of the flow field are consistent with the experimental results.

The proposed method significantly reduces the optimization time, has higher efficiency and solves the problem that traditional optimization methods struggle with, which is ensuring optimal flow regulation performance. Compared to the traditional trial-and-error optimization method, the proposed method is more effective. The feasibility of the method is supported by experimental results.

The development of a sociological theory is a process which can often only reach a temporary conclusion. A new theory's potential and an old theory's stagnation are invariably a matter either of solved problems which require a new theoretical construction or of the old theory failing which means that a new one is needed. The anomie theory finds itself precisely in that stage of its development in which the old concept for explaining the current “social facts” is considered unsatisfactory, yet more promising prospects are not yet clearly in view. This, therefore, is our objective, to attempt to provide the anomie theory with new insights and meaning.

The incredible tempo of the ongoing process of social change in the People's Republic of China has led to profound shifting and reorganization in society. The social structure has become more complex and diversified, new social groups have emerged such as private business people and migrant workers. The gap between the wealthy and the poor is increasing and structures determining status and income are widely divergent.

In fall 1994 a group of social scientists from different parts in the world met in Switzerland. The Swiss Academy for Development (SAD) organized a symposium to discuss problems of contemporary developmental policy and research. The meeting focussed on the upcoming World Summit of Social Development in Copenhagen in 1995 and so the participants intended to present themes of international interest that would be introduced to a greater audience. The important contributions and propositions of this symposium are found in this publication.

This paper presents the application of grey modeling for thermal spray processing parameter analysis in less data environment.

Based on processing knowledge, key processing parameters of thermal spray process are analyzed and preselected. Then, linear and non-linear grey modeling models are integrated to mine the relationships between different processing parameters.

Model A reveals the linear correlation between the HVOF process parameters and the characterization of particle in-flight with average relative errors of 9.230 percent and 5.483 percent for velocity and temperature.

The prediction accuracies of coatings properties vary, which means that there exists more complex non-linear relationship between the identified input parameters and coating results, or more unexpected factors (e.g. factors from material side) should be further investigated.

According to the modeling case in this paper, method has potential to deal with other diverse modeling problems in different industrial applications where challenge to collecting large quantity of data sets exists.

It is the first time to apply grey modeling for thermal spray processing where complicated relationships among processing parameters exist. The modeling results show reasonable results to experiment and existing processing knowledge.

This study aims to identify and analyse the gains and strains associated with flexible working practices (FWPs) introduced and adopted prior to and during the pandemic and consider how these experiences are likely to shape the future of workplace flexibility post-pandemic.

A case study research strategy was adopted to explore the FWPs implemented by a state-owned organisation in the Chinese publishing industry. A mixed data collection method was used. Quantitative data was collected from 50 valid questionnaires, which was followed by 7 qualitative interviews to gain rich insights into the availability and effectiveness of various FWPs and associated benefits and drawbacks.

While the results confirm positive effects FWPs have on employee engagement and retention and on business continuity and employee well-being during the pandemic, the empirical analysis highlights the performance-driven patterns in use and impacts of some FWPs, which caused concerns and dilemmas. Besides the increasing intense market competition, the changing face of state-owned enterprises and managerial attitudes have been found to have significant effects on the use of FWPs.

This paper has contributed to a better understanding of flexible working in an under-researched setting, reflected in changes before and during the pandemic, offering an insight into the commercialised nature of flexible working in the Chinese context. It has implications for organisations and HR practitioners as they envision future workplace flexibility.

In the field of global leadership, much of the research has focused on uncovering competencies and methods for assessing competencies. The process of developing global leaders has been researched less frequently; however, it is widely accepted that this process involves learning on the part of the leader. Mezirow’s (1978, 1991) transformative learning is a special type of learning in the domain of adult education and a useful lens to better understand the disorienting triggers that are thought to induce global leadership development (GLD). In simple terms, a disorienting experience occurs when we discover that something we thought was certain is now uncertain. Conducting business in another country or merely navigating to a grocery store or restaurant there can be a disorienting experience. In these situations, people are exposed to new information that does not fit their current meaning structures or thought paradigms, and at this juncture, people have a choice: to transform their perspective or remain unchanged. When individuals transform their perspective, they are experiencing transformative learning. The first section of this chapter reviews the concept of disorienting experiences across disciplines and within the domain of learning and education. The second section explains three GLD process models with a special focus on the role played by disorienting trigger events in each one. The final section explains the Disorientation Index (Ensign, 2019), which articulates dimensions of trigger events. The chapter concludes with future research directions and practical implications.

This chapter adopts a problem-solving perspective to analyze the competitive dynamics of innovation ecosystems. We argue that features such as uncertainty, complexity, and ambiguity, entail different knowledge requirements which explain the varying abilities of focal firms to coordinate the ecosystem and benefit from the activities of their suppliers, complementors, and users. We develop an analytical framework to interpret various instances of coupling patterns and identify four archetypical types of innovation ecosystems.

With continuous concerning on the toxic of element Pb, Pb-free solder was gradually used to replace traditional Sn-Pb solder. However, during the transition period from Sn-Pb to Pb-free solder, mixing of Sn-Pb and Pb-free is inevitable occurred in certain products, and in China where Sn-Pb solder was still used extensively in certain areas especially. Correspondingly, understanding reliability of Sn-Pb solder joints was very important, and further studies were needed.

Thermal shock test between −55°C and 125 °C was conducted on Sn-37Pb solder bumps in the BGA package to investigate the microstructure evolution and the growth mechanism of interfacial intermetallic compound (IMC) layer. The effects of thermal shock on the mechanical property and fracture behavior of Sn-37Pb solder bumps were discussed.

Pb-rich phase was coarsened and voids were increased at first; Pb-rich phase was refined and voids were decreased secondly with the increase of thermal shock cycles; the shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67MPa at 2,000 cycles; interfacial IMCs of solder bumps was from typical scallop-type into smooth, the composition of IMCs was from Cu₆Sn₅ into Cu₆Sn₅ and Cu₃S_n after thermal shock with 1,500 and 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure respectively.

Compared with the board level test method, the impact shear test for the single solder bump is more convenient and economical and is actively pursued by the industries. The shear strength of solder bumps was slightly decreased after thermal shock, but was back up to 73.67 MPa at 2,000 cycles; 20.0 per cent of solder bumps at 1,500 cycles and 9.5 per cent of solder bumps at 2,000 cycles were failure.